Global Ne)lix Replacing Datacenter
Oracle with Global Apache Cassandra on AWS October 24th, 2011 Adrian Cockcro6 @adrianco #ne9lixcloud h=p://www.linkedin.com/in/adriancockcro6

Ne9lix Inc. With over
25 million members in the United States, Canada and La8n America, Ne<lix, Inc. is the worlds leading Internet subscrip8on service for enjoying movies and TV shows. Interna8onal Expansion Ne<lix, Inc., the leading global Internet movie subscrip8on service, today announced it will expand to the United Kingdom and Ireland in early 2012. Source: h=p://ir.ne9lix.com

Building a Global Ne9lix Service
Ne9lix Cloud MigraLon Highly Available and Globally Distributed Data Scalability and Performance

Why Use Public Cloud?

Things We Don’t Do

Be=er Business Agility

Data Center Ne9lix could
not build new datacenters fast enough Capacity growth is acceleraLng, unpredictable Product launch spikes -­‐ iPhone, Wii, PS3, XBox

Out-­‐Growing Data Center h=p://techblog.ne9lix.com/2011/02/redesigning-­‐ne9lix-­‐api.html
37x Growth Jan 2010-­‐Jan 2011 Datacenter Capacity

Ne9lix.com is now ~100% Cloud
A few small back end data sources sLll in progress All internaLonal product is cloud based USA specific logisLcs remains in the Datacenter Working aggressively on billing, PCI compliance on AWS

Ne9lix Choice was AWS with
our own pla9orm and tools Unique pla9orm requirements and extreme agility and flexibility

Leverage AWS Scale “the
biggest public cloud” AWS investment in features and automaLon Use AWS zones and regions for high availability, scalability and global deployment

We want to use clouds,
we don’t have Lme to build them Public cloud for agility and scale AWS because they are big enough to allocate thousands of instances per hour when we need to

Ne9lix Deployed on AWS Content
Logs Play WWW API Video S3 DRM Sign-­‐Up Metadata Masters EMR CDN Device EC2 Search Hadoop rouLng Config Movie TV Movie S3 Hive Bookmarks Choosing Choosing Business Mobile CDN Logging RaLngs Intelligence iPhone

Datacenter AnL-­‐Pa=erns What did
we do in the datacenter that prevented us from meeLng our goals?

Old Datacenter vs. New Cloud
Arch Central SQL Database Distributed Key/Value NoSQL SLcky In-­‐Memory Session Shared Memcached Session Cha=y Protocols Latency Tolerant Protocols Tangled Service Interfaces Layered Service Interfaces Instrumented Code Instrumented Service Pa=erns Fat Complex Objects Lightweight Serializable Objects Components as Jar Files Components as Services

The Central SQL Database •
Datacenter has central Oracle databases – Everything in one place is convenient unLl it fails – Customers, movies, history, configuraLon • Schema changes require downLme An8-­‐paOern impacts scalability, availability

The Distributed Key-­‐Value Store •
Cloud has many key-­‐value data stores – More complex to keep track of, do backups etc. – Each store is much simpler to administer – Joins take place in java code DBA • No schema to change, no scheduled downLme • Latency for typical queries – Memcached is dominated by network latency <1ms – Cassandra replicaLon takes a few milliseconds – Oracle for simple queries is a few milliseconds – SimpleDB replicaLon and REST auth overheads >10ms

Data MigraLon to Cassandra

TransiLonal Steps • BidirecLonal ReplicaLon
– Oracle to SimpleDB – Queued reverse path using SQS – Backups remain in Datacenter via Oracle • New Cloud-­‐Only Data Sources – Cassandra based – No replicaLon to Datacenter – Backups performed in the cloud

API AWS EC2 Front
End Load Balancer Discovery Service API Proxy API etc. Load Balancer Component API SQS Services Oracl e Oracle Oracle Cassandra memcached ReplicaLon memcached EC2 Internal Disks Ne)lix S3 Data Center SimpleDB

Cuong the Umbilical • TransiLon
Oracle Data Sources to Cassandra – Offload Datacenter Oracle hardware – Free up capacity for growth of remaining services • TransiLon SimpleDB+Memcached to Cassandra – Primary data sources that need backup – Keep simplest small use cases for now • New challenges – Backup, restore, archive, business conLnuity – Business Intelligence integraLon

API AWS EC2 Front
End Load Balancer Discovery Service API Proxy Load Balancer Component API Services memcached Cassandra EC2 Internal Disks Backup S3 SimpleDB

High Availability • Cassandra stores
3 local copies, 1 per zone – Synchronous access, durable, highly available – Read/Write One fastest, least consistent -­‐ ~1ms – Read/Write Quorum 2 of 3, consistent -­‐ ~3ms • AWS Availability Zones – Separate buildings – Separate power etc. – Close together

Cassandra Write Data Flows
Single Region, MulLple Availability Zone Cassandra • Disks • Zone A 2 2 4 2 1. Client Writes to any Cassandra 3 3 Cassandra If a node goes offline, Cassandra Node • Disks 5 • Disks 5 hinted handoff 2. Coordinator Node • Zone C 1 • Zone A completes the write replicates to nodes when the node comes and Zones back up. 3. Nodes return ack to Clients coordinator Requests can choose to 4. Coordinator returns 3 wait for one node, a Cassandra Cassandra ack to client • Disks • Disks 5 quorum, or all nodes to 5. Data wri=en to • Zone C • Zone B ack the write internal commit log disk Cassandra SSTable disk writes and • Disks • Zone B compacLons occur asynchronously

Data Flows for MulL-­‐Region Writes
Consistency Level = Local Quorum 1. Client Writes to any If a node or region goes offline, hinted handoff Cassandra Node completes the write when the node comes back up. 2. Coordinator node replicates Nightly global compare and repair jobs ensure to other nodes Zones and everything stays consistent. regions 3. Local write acks returned to coordinator 100+ms latency Cassandra 2 7 4. Client gets ack when 2 of 3 Cassandra • Disks • Disks 8 2 2 • Zone A 4 2 6 6 • Zone A local nodes are commi=ed Cassandra 3 3 Cassandra 7 Cassandra Cassandra 5 5 5. Data wri=en to internal 8 • Disks • Disks • Disks • Disks • Zone C • Zone A • Zone C • Zone A 1 commit log disks US EU 6. When data arrives, remote Clients Clients Cassandra 3 Cassandra Cassandra 7 Cassandra node replicates data • Disks • Zone C • Disks • Zone B 5 • Disks • Zone C • Disks • Zone B 8 7. Ack direct to source region Cassandra Cassandra coordinator • Disks • Disks • Zone B • Zone B 8. Remote copies wri=en to commit log disks

Remote Copies • Cassandra duplicates
across AWS regions – Asynchronous write, replicates at desLnaLon – Doesn’t directly affect local read/write latency • Global Coverage – Business agility – Follow AWS… • Local Access 3 3 – Be=er latency 3 3 – Fault IsolaLon

Cassandra Backup • Full Backup
Cassandra – Time based snapshot Cassandra Cassandra – SSTable compress -­‐> S3 Cassandra Cassandra • Incremental S3 – SSTable write triggers Cassandra Backup Cassandra compressed copy to S3 • ConLnuous OpLon Cassandra Cassandra – Scrape commit log Cassandra Cassandra – Write to EBS every 30s

Cassandra Restore • Full Restore
Cassandra Cassandra Cassandra – Replace previous data • New Ring from Backup Cassandra Cassandra – New name old data S3 Backup Cassandra Cassandra • Scripted – Create new instances Cassandra Cassandra – Parallel load -­‐ fast Cassandra Cassandra

Cassandra Online AnalyLcs • Brisk
= Hadoop + Cass Cassandra Brisk Cassandra – Use split Brisk ring – Size each separately Brisk Cassandra • Direct Access S3 Backup Cassandra Cassandra – Keyspaces – Hive/Pig/Map-­‐Reduce Cassandra Cassandra – Hdfs as a keyspace Cassandra Cassandra – Distributed namenode

Cassandra Archive Appropriate level
of paranoia needed… • Archive could be un-­‐readable – Restore S3 backups weekly from prod to test • Archive could be stolen – PGP Encrypt archive • AWS East Region could have a problem – Copy data to AWS West • ProducLon AWS Account could have an issue – Separate Archive account with no-­‐delete S3 ACL • AWS S3 could have a global problem – Create an extra copy on a different cloud vendor

Tools and AutomaLon • Developer
and Build Tools – Jira, Perforce, Eclipse, Jenkins, Ivy, ArLfactory – Builds, creates .war file, .rpm, bakes AMI and launches • Custom Ne9lix ApplicaLon Console – AWS Features at Enterprise Scale (hide the AWS security keys!) – Auto Scaler Group is unit of deployment to producLon • Open Source + Support – Apache, Tomcat, Cassandra, Hadoop, OpenJDK, CentOS – Datastax support for Cassandra, AWS support for Hadoop via EMR • Monitoring Tools – Datastax Opscenter for monitoring Cassandra – AppDynamics – Developer focus for cloud h=p://appdynamics.com

Developer MigraLon • Detailed SQL
to NoSQL TransiLon Advice – Sid Anand -­‐ QConSF Nov 5th – Ne9lix’ TransiLon to High Availability Storage Systems – Blog -­‐ h=p://pracLcalcloudcompuLng.com/ – Download Paper PDF -­‐ h=p://bit.ly/bhOTLu • Mark Atwood, "Guide to NoSQL, redux” – YouTube h=p://youtu.be/zAbFRiyT3LU

Cloud OperaLons Cassandra Use
Cases Model Driven Architecture Performance and Scalability

Cassandra Use Cases • Key
by Customer – Cross-­‐region clusters – Many app specific Cassandra clusters, read-­‐intensive – Keys+Rows in memory using m2.4xl Instances • Key by Customer:Movie – e.g. Viewing History – Growing fast, write intensive – m1.xl instances – Keys cached in memory, one cluster per region • Large scale data logging – lots of writes – Column data expires a6er Lme period – Distributed counters, one cluster per region

Model Driven Architecture • Datacenter
PracLces – Lots of unique hand-­‐tweaked systems – Hard to enforce pa=erns • Model Driven Cloud Architecture – Perforce/Ivy/Jenkins based builds for everything – Every producLon instance is a pre-­‐baked AMI – Every applicaLon is managed by an Autoscaler Every change is a new AMI

Ne9lix Pla9orm Cassandra AMI •
Tomcat server – Always running, registers with pla9orm – Manages Cassandra state, tokens, backups • Removed Root Disk Dependency on EBS – Use S3 backed AMI for stateful services – Normally use EBS backed AMI for fast provisioning

Chaos Monkey • Make sure
systems are resilient – Allow any instance to fail without customer impact • Chaos Monkey hours – Monday-­‐Thursday 9am-­‐3pm random instance kill • ApplicaLon configuraLon opLon – Apps now have to opt-­‐out from Chaos Monkey • Computers (Datacenter or AWS) randomly die – Fact of life, but too infrequent to test resiliency

AppDynamics Monitoring of Cassandra –
AutomaLc Discovery

Ne9lix ContribuLons to Cassandra •
Cassandra as a mutable toolkit – Cassandra is in Java, pluggable, well structured – Ne9lix has a building full of Java engineers…. • Actual ContribuLons delivered in 0.8 – First prototype of off-­‐heap row cache – Incremental backup SSTable write callback • Work In Progress – AWS integraLon and backup using Tomcat helper – Astyanax re-­‐write of Hector Java client library

Performance TesLng • Cloud Based
TesLng – fricLonless, elasLc – Create/destroy any sized cluster in minutes – Many test scenarios run in parallel • Test Scenarios – Internal app specific tests – Simple “stress” tool provided with Cassandra • Scale test, keep making the cluster bigger – Check that tooling and automaLon works… – How many ten column row writes/sec can we do?

<DrEvil>ONE MILLION</DrEvil>

Scale-­‐Up Linearity Client Writes/s
by node count – ReplicaEon Factor = 3 1200000 1099837 1000000 800000 600000 537172 400000 366828 200000 174373 0 0 50 100 150 200 250 300 350

Per Node AcLvity Per
Node 48 Nodes 96 Nodes 144 Nodes 288 Nodes Per Server Writes/s 10,900 w/s 11,460 w/s 11,900 w/s 11,456 w/s Mean Server Latency 0.0117 ms 0.0134 ms 0.0148 ms 0.0139 ms Mean CPU %Busy 74.4 % 75.4 % 72.5 % 81.5 % Disk Read 5,600 KB/s 4,590 KB/s 4,060 KB/s 4,280 KB/s Disk Write 12,800 KB/s 11,590 KB/s 10,380 KB/s 10,080 KB/s Network Read 22,460 KB/s 23,610 KB/s 21,390 KB/s 23,640 KB/s Network Write 18,600 KB/s 19,600 KB/s 17,810 KB/s 19,770 KB/s Node specificaLon – Xen Virtual Images, AWS US East, three zones • Cassandra 0.8.6, CentOS, SunJDK6 • AWS EC2 m1 Extra Large – Standard price $ 0.68/Hour • 15 GB RAM, 4 Cores, 1Gbit network • 4 internal disks (total 1.6TB, striped together, md, XFS)

Time is Money 48
nodes 96 nodes 144 nodes 288 nodes Writes Capacity 174373 w/s 366828 w/s 537172 w/s 1,099,837 w/s Storage Capacity 12.8 TB 25.6 TB 38.4 TB 76.8 TB Nodes Cost/hr $32.64 $65.28 $97.92 $195.84 Test Driver Instances 10 20 30 60 Test Driver Cost/hr $20.00 $40.00 $60.00 $120.00 Cross AZ Traffic 5 TB/hr 10 TB/hr 15 TB/hr 301 TB/hr Traffic Cost/10min $8.33 $16.66 $25.00 $50.00 Setup DuraLon 15 minutes 22 minutes 31 minutes 662 minutes AWS Billed DuraLon 1hr 1hr 1 hr 2 hr Total Test Cost $60.97 $121.94 $182.92 $561.68 1 EsLmate two thirds of total network traffic 2 Workaround for a tooling bug slowed setup

Takeaway Ne<lix is
using Cassandra on AWS as a key infrastructure component of its globally distributed streaming product. Also, benchmarking in the cloud is fast, cheap and scalable h=p://www.linkedin.com/in/adriancockcro6 @adrianco #ne9lixcloud acockcro6@ne9lix.com

Amazon Cloud Terminology Reference See
http://aws.amazon.com/ This is not a full list of Amazon Web Service features• AWS – Amazon Web Services (common name for Amazon cloud) • AMI – Amazon Machine Image (archived boot disk, Linux, Windows etc. plus applicaLon code) • EC2 – ElasLc Compute Cloud – Range of virtual machine types m1, m2, c1, cc, cg. Varying memory, CPU and disk configuraLons. – Instance – a running computer system. Ephemeral, when it is de-­‐allocated nothing is kept. – Reserved Instances – pre-­‐paid to reduce cost for long term usage – Availability Zone – datacenter with own power and cooling hosLng cloud instances – Region – group of Availability Zones – US-­‐East, US-­‐West, EU-­‐Eire, Asia-­‐Singapore, Asia-­‐Japan • ASG – Auto Scaling Group (instances booLng from the same AMI) • S3 – Simple Storage Service (h=p access) • EBS – ElasLc Block Storage (network disk filesystem can be mounted on an instance) • RDS – RelaLonal Database Service (managed MySQL master and slaves) • SDB – Simple Data Base (hosted h=p based NoSQL data store) • SQS – Simple Queue Service (h=p based message queue) • SNS – Simple NoLficaLon Service (h=p and email based topics and messages) • EMR – ElasLc Map Reduce (automaLcally managed Hadoop cluster) • ELB – ElasLc Load Balancer • EIP – ElasLc IP (stable IP address mapping assigned to instance or ELB) • VPC – Virtual Private Cloud (extension of enterprise datacenter network into cloud) • IAM – IdenLty and Access Management (fine grain role based security keys)